It is the long-range purpose of this project to study the natural history of chronic lymphocytic leukemia, to define those disease parameters which indicate the need for early therapeutic intervention, and to investigate new therapeutic approaches which will improve the quantity and quality of survival. BIBLIOGRAPHIC REFERENCES: Johnson, R.E.: Role of radiation therapy in management of adult leukemia. Cancer 39: 852-855, 1977. Johnson, R.E.: Radiotherapy as primary treatment for chronic lymphocytic leukemia. Clin. Haematol. 6: 237-244, 1977.